Process for preparing alkanolamines by homogeneously catalyzed alcohol amination

ABSTRACT

Process for preparing alkanolamines which have a primary amino group (—NH 2 ) and a hydroxyl group (—OH) by alcohol amination of diols having two hydroxyl groups (—OH) by means of ammonia with elimination of water, wherein the reaction is carried out homogeneously catalyzed in the presence of at least one complex catalyst comprising at least one element selected from groups 8, 9 and 10 of the Periodic Table and also at least one donor ligand.

This patent application claims the benefit of U.S. provisional patent application Ser. No. 61/450,156 filed on Mar. 8, 2011, incorporated in its entirety herein by reference.

The present invention relates to a process for preparing alkanolamines by homogeneously catalyzed alcohol amination of diols by means of ammonia with elimination of water in the presence of a complex catalyst which comprises at least one element selected from groups 8, 9 and 10 of the Periodic Table and also at least one phosphorus donor ligand.

Alkanolamines are compounds which have a primary amino group (—NH₂) and a hydroxyl group (—OH).

Alkanolamines are valuable products having many different uses, for example solvents, stabilizers, for the synthesis of chelating agents, as starting materials for the production of synthetic resins, drugs, inhibitors, corrosion inhibitors, polyurethanes, as hardeners for epoxy resins, as surface-active substances and for gas scrubbing.

The amination of diols by means of secondary amines using homogeneous iridium and ruthenium catalysts to form amino alcohols and linear diamines having tertiary amino groups has been described, for example, in EP 239 934; J. A. Marsella, J. Org. Chem. 1987, 52, 467-468; U.S. Pat. No. 4,855,425; K.-T. Huh, Bull. Kor. Chem. Soc. 1990, 11, 45-49; N. Andrushko, V. Andrushko, P. Roose, K. Moonen, A. Börner, ChemCatChem, 2010, 2, 640-643 and S. Bähn, A. Tillack, S. Imm, K. Mevius, D. Michalik, D. Hollmann, L. Neubert, M. Beller, ChemSusChem 2009, 2, 551-557. In these studies, the amination is carried out at 100-180° C.

J. A. Marsella, J. Organomet. Chem. 1991, 407, 97-105 and B. Blank, S. Michlik, R. Kempe, Adv. Synth. Catal. 2009, 351, 2903-2911; G. Jenner, G. Bitsi, J. Mol. Cat, 1988, 45, 165-168; Y. Z. Youn, D. Y. Lee, B. W. Woo, J. G. Shim, S. A. Chae, S. C. Shim, J. Mol. Cat, 1993, 79, 39-45; K. I. Fujita, R. Yamaguchi, Synlett, 2005, 4, 560-571; K. I. Fujii, R. Yamaguchi, Org. Lett. 2004, 20, 3525-3528; K. I. Fujita, K. Yamamoto, R. Yamaguchi, Org. Lett. 2002, 16, 2691-2694; A. Nova, D. Balcells, N. D. Schley, G. E. Dobereiner, R. H. Crabtree, O. Eisenstein, Organometallics DOI: 10.1021/om101015u; and M. H. S. A. Hamid, C. L. Allen, G. W. Lamb, A. C. Maxwell, H. C. Maytum, A. J. A. Watson, J. M. J. Williams, J. Am. Chem. Soc. 2009, 131, 1766-1774 and O. Saidi, A. J. Blacker, G. W. Lamb, S. P. Marsden, J. E. Taylor, J. M. J. Williams, Org. Proc. Res. Dev. 2010, 14, 1046-1049 describe the amination of diols by means of primary amines using homogeneously dissolved ruthenium- and iridium-based transition metal catalysts. However, the cyclic compounds and not the desired alkanolamines are formed here. The economically attractive amination of diols by means of ammonia to form alkanolamines has not been described for these systems.

EP 0 234 401 A1 describes the reaction of ethylene glycol with ammonia in the presence of a ruthenium carbonyl compound. In the process described in EP 0 234 401 A1, the monoamination product (monoethanolamine) is formed among other things. In addition, large amounts of the secondary and tertiary amines (diethanolamine and triethanolamine) and cyclic products (N-(hydroxyethyl)piperazine and N,N′-bis(hydroxyethyl)piperazine) are formed as by-products.

All the above-described processes for the reaction of diols have the disadvantage that undesired secondary, tertiary and cyclic amines are formed to a major extent in addition to the desired alkanolamines.

It is an object of the present invention to provide a process for preparing alkanolamines by alcohol amination of diols by means of ammonia with elimination of water.

The object is achieved by a process for preparing alkanolamines which have a primary amino group (—NH₂) and a hydroxyl group (—OH) by alcohol amination of diols having two hydroxyl groups (—OH) by means of ammonia with elimination of water, wherein the reaction is carried out homogeneously catalyzed in the presence of at least one complex catalyst comprising at least one element selected from groups 8, 9 and 10 of the Periodic Table and also at least one phosphorus donor ligand.

It has surprisingly been found that alkanolamines can be obtained by the homogeneously catalyzed amination of diols by means of ammonia with elimination of water using the complex catalysts which are used in the process of the invention and comprise at least one element selected from groups 8, 9 and 10 of the Periodic Table and also at least one phosphorus donor ligand. The process of the invention has the advantage that it gives alkanolamines in considerably improved yields compared to the processes described in the prior art. In addition, the formation of undesired by-products such as secondary and tertiary amines and also cyclic amines is largely avoided.

Starting Materials

In the process of the invention, starting materials having two hydroxyl groups are used.

Suitable starting materials are virtually all diols which meet the above-mentioned prerequisites. The diols can be straight-chain, branched or cyclic. The alcohols can also bear substituents which are inert under the reaction conditions of the alcohol amination, for example alkoxy, alkenyloxy, alkylamino, dialkylamino and halogens (F, Cl, Br, I).

Suitable starting materials which can be used in the process of the invention are, for example, diols which have a functional group of the formula (—CH₂—OH) and a further hydroxyl group (—OH).

In addition, diols having two functional groups of the formula (—CH₂—OH) are suitable.

As starting materials, it is possible to use all known diols. Preference is given to diols which have at least one functional group of the formula (—CH₂—OH). Greater preference is given to diols which have two functional groups of the formula (—CH₂—OH). Examples of diols which can be used as starting materials in the process of the invention are 1,2-ethanediol (ethylene glycol), 1,2-propanediol (1,2-propylene glycol), 1,3-propanediol (1,3-propylene glycol), 1,4-butanediol (1,4-butylene glycol), 1,2-butanediol (1,2-butylene glycol), 2,3-butanediol, 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol (neopentyl glycol), 1,5-pentanediol, 1,2-pentanediol, 1,6-hexanediol, 1,2-hexanediol, 1,7-heptanediol, 1,2-heptanediol, 1,8-octanediol, 1,2-octanediol, 1,9-nonanediol, 1,2-nonanediol, 2,4-dimethyl-2,5-hexanediol, the neopentyl glycol ester of hydroxypivalic acid, diethylene glycol, triethylene glycol, 2-butene-1,4-diol, 2-butyne-1,4-diol, polyethylene glycols, polypropylene glycols such as 1,2-polypropylene glycol and 1,3-polypropylene glycol, polytetrahydrofuran, diethanolamine, 1,4-bis(2-hydroxyethyl)piperazine, diisopropanolamine, N-butyldiethanolamine, N-methyldiethanolamine, 1,10-decanediol, 1,12-dodecanediol, 2,5-(dimethanol)-furan and C36-diol (mixture of isomers of alcohols having the empirical formula C₃₆H₇₄O₂).

Another name for 2,5-(dimethanol)-furan is 2,5-bis(hydroxymethyl)-furan.

Further suitable starting materials are diols of the general formulae (XXXI), (XXXII) and (XXXIII):

where

-   -   n1 is 2-30;     -   n2 is 1-30 and     -   n3 is 1-30.

Preference is given to diols having two functional groups of the formula (—CH₂—OH).

Particularly preferred diols are 1,2-ethanediol (ethylene glycol), 1,2-propanediol (1,2-propylene glycol), 1,3-propanediol (1,3-propylene glycol), 1,4-butanediol (1,4-butylene glycol), 1,2-butanediol (1,2-butylene glycol), 2,3-butanediol, 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol (neopentyl glycol), diethylene glycol, triethylene glycol, polyethylene glycols, polypropylene glycols such as 1,2-polypropylene glycol and 1,3-polypropylene glycol, polytetrahydrofuran, 2,5-(dimethanol)-furan and diethanolamine.

Complex Catalyst

In the process of the invention, at least one complex catalyst comprising at least one element selected from groups 8, 9 and 10 of the Periodic Table (IUPAC nomenclature) and also at least one donor ligand is used. The elements of groups 8, 9 and 10 of the Periodic Table comprise iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium and platinum. Preference is given to complex catalysts which comprise at least one element selected from among ruthenium and iridium.

In one embodiment, the process of the invention is carried out homogeneously catalyzed in the presence of at least one complex catalyst of the general formula (I):

-   -   where     -   L¹ and L² are each, independently of one another, phosphine         (PR^(a)R^(b)), amine (NR^(a)R^(b)), sulfide, SH, sulfoxide         (S(═O)R), C₅-C₁₀-heteroaryl comprising at least one heteroatom         selected from among nitrogen (N), oxygen (O) and sulfur (S),         arsine (AsR^(a)R^(b)), stibane (SbR^(a)R^(b)) and N-heterocyclic         carbenes of the formula (II) or (III):

-   -   L³ is a monodentate two-electron donor selected from the group         consisting of carbon monoxide (CO), PR^(a)R^(b)R^(c), NO⁺,         AsR^(a)R^(b)R^(c), SbR^(a)R^(b)R^(c), SR^(a)R^(b), nitrile         (RCN), isonitrile (RNC), nitrogen (N₂), phosphorus trifluoride         (PF₃), carbon monosulfide (CS), pyridine, thiophene,         tetrahydrothiophene and N-heterocyclic carbenes of the         formula (II) or (III);     -   R¹ and R² are both hydrogen or together with the carbon atoms to         which they are bound form a phenyl ring which together with the         quinolinyl unit of the formula I forms an acridinyl unit;     -   R, R^(a), R^(b), R^(c), R³, R⁴ and R⁵ are each, independently of         one another, unsubstituted or at least monosubstituted         C₁-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl comprising at least one         heteroatom selected from among N, O and S, C₅-C₁₀-aryl or         C₅-C₁₀-heteroaryl comprising at least one heteroatom selected         from among N, O and S,         -   where the substituents are selected from the group             consisting of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl;     -   Y is a monoanionic ligand selected from the group consisting of         H, F, Cl, Br, I, OCOR, OCOCF₃, OSO₂R, OSO₂CF₃, CN, OH, OR and         N(R)₂ or an uncharged molecule selected from the group         consisting of NH₃, N(R)₃ and R₂NSO₂R;     -   X¹ represents one, two, three, four, five, six or seven         substituents on one or more atoms of the acridinyl unit or one,         two, three, four or five substituents on one or more atoms of         the quinolinyl unit,         -   where the radicals X¹ are selected independently from the             group consisting of hydrogen, F, Cl, Br, I, OH, NH₂, NO₂,             —NC(O)R, C(O)NR₂, —OC(O)R, —C(O)OR, CN and borane             derivatives which can be obtained from the catalyst of the             formula I by reaction with NaBH₄ and unsubstituted or at             least monosubstituted C₁-C₁₀-alkoxy, C₁-C₁₀-alkyl,             C₃-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl comprising at least             one heteroatom selected from among N, O and S, C₅-C₁₀-aryl             and C₅-C₁₀-heteroaryl comprising at least one heteroatom             selected from among N, O and S,         -   where the substitutents are selected from the group             consisting of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl;     -   and     -   M is iron, cobalt, nickel, ruthenium, rhodium, palladium,         osmium, iridium or platinum.

It should be pointed out here that the complex catalyst of the formula (I) bears a positive charge when Y is an uncharged molecule selected from the group consisting of NH₃, NR₃, R₂NSO₂R and M is selected from the group consisting of ruthenium, nickel, palladium and iron.

In a preferred embodiment, the process of the invention is carried out in the presence of at least one homogeneously dissolved complex catalyst of the formula (I), where the substituents have the following meanings:

-   L¹ and L², are each, independently of one another, PR^(a)R^(b),     NR^(a)R^(b), sulfide, SH, S(═O)R, C₅-C₁₀-heteroaryl comprising at     least one heteroatom selected from among N, O and S; -   L³ is a monodentate two-electron donor selected from the group     consisting of CO, PR^(a)R^(b)R^(c), NO⁺, RCN, RNC, N₂, PF₃, CS,     pyridine, thiophene and tetrahydrothiophene; -   R¹ and R² are both hydrogen or together with the carbon atoms to     which they are bound form a phenyl ring which together with the     quinolinyl unit of the formula (I) forms an acridinyl unit; -   R, R^(a), R^(b), R^(c), R³, R⁴ and R⁵ are each, independently of one     another, unsubstituted C₁-C₁₀-alkyl, C₃-C₁₀-cycloalkyl,     C₃-C₁₀-heterocyclyl comprising at least one heteroatom selected from     among N, O and S, C₅-C₁₀-aryl or C₅-C₁₀-heteroaryl comprising at     least one heteroatom selected from among N, O and S; -   Y is a monoanionic ligand selected from the group consisting of H,     F, Cl, Br, OCOR, OCOCF₃, OSO₂R, OSO₂CF₃, CN, OH, OR and N(R)₂; -   X¹ represents one, two, three, four, five, six or seven substituents     on one or more atoms of the acridinyl unit or one, two, three, four     or five substituents on one or more atoms of the quinolinyl unit,     -   where X¹ is selected independently from the group consisting of         hydrogen, F, Cl, Br, I, OH, NH₂, NO₂, —NC(O)R, C(O)NR₂, —OC(O)R,         —C(O)OR, CN and borane derivatives which can be obtained from         the catalyst of the formula (I) by reaction with NaBH₄ and         unsubstituted C₁-C₁₀-alkoxy, C₁-C₁₀-alkyl, C₃-C₁₀-cycloalkyl,         C₃-C₁₀-heterocyclyl comprising at least one heteroatom selected         from among N, O and S, C₅-C₁₀-aryl and C₅-C₁₀-heteroaryl         comprising at least one heteroatom selected from among N, O and         S;         and -   M is ruthenium or iridium.

In a further preferred embodiment, the process of the invention is carried out in the presence of at least one homogeneously dissolved complex catalyst where R¹ and R² are both hydrogen and the complex catalyst is a catalyst of the formula (IV):

and X¹, L¹, L², L³ and Y are as defined above.

In a further preferred embodiment, the process of the invention is carried out in the presence of at least one homogeneously dissolved complex catalyst where R¹ and R² together with the carbon atoms to which they are bound form a phenyl ring which together with the quinolinyl unit of the formula (I) forms an acridinyl unit and the complex catalyst is a catalyst of the formula (V):

and X¹, L¹, L², L³ and Y are as defined above.

Some complex catalysts (formulae (VI), (VII), (VIII), (IX), (X), (XI), (XII) and (XIII)) which can be used in the process of the invention are shown by way of example below:

In a further preferred embodiment, the process of the invention is carried out in the presence of at least one complex catalyst selected from the group of catalysts of the formulae (VI), (VII), (VIII), (IX), (X), (XI), (XII) and (XIII), where

-   R^(a) and R^(b) are each, independently of one another,     unsubstituted or at least monosubstituted C₁-C₁₀-alkyl,     C₃-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl comprising at least one     heteroatom selected from among N, O and S, C₅-C₁₀-aryl or     C₅-C₁₀-heteroaryl comprising at least one heteroatom selected from     among N, O and S,     -   where the substituents are selected from the group consisting         of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl; -   Y is a monoanionic ligand selected from the group consisting of H,     F, Cl, Br, OCOR, OCOCF₃, OSO₂R, OSO₂CF₃, CN, OH, OR, N(R)₂; -   R is unsubstituted or at least monosubstituted C₁-C₁₀-alkyl,     C₃-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl comprising at least one     heteroatom selected from among N, O and S, C₅-C₁₀-aryl,     C₅-C₁₀-heteroaryl comprising at least one heteroatom selected from     among N, O and S,     -   where the substituents are selected from the group consisting         of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl; -   X¹ represents one, two or three substituents on one or more atoms of     the acridinyl unit or one or two substituents on one or more atoms     of the quinolinyl unit,     -   where the radicals X¹ are selected independently from the group         consisting of hydrogen, F, Cl, Br, I, OH, NH₂, NO₂, —NC(O)R,         C(O)NR₂, —OC(O)R, —C(O)OR, CN and borane derivatives which can         be obtained from the catalyst of the formula I by reaction with         NaBH₄ and unsubstituted C₁-C₁₀-alkoxy, C₁-C₁₀-alkyl,         C₃-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl comprising at least one         heteroatom selected from among N, O and S, C₅-C₁₀-aryl and         C₅-C₁₀-heteroaryl comprising at least one heteroatom selected         from among N, O and S;         and -   M is ruthenium or iridium.

In a further preferred embodiment, the process of the invention is carried out in the presence of at least one complex catalyst selected from the group consisting of catalysts of the formulae (VI), (VII), (VIII), (IX), (X), (XI), (XII) and (XIII), where

-   R^(a) and R^(b) are each, independently of one another, methyl,     ethyl, isopropyl, tert-butyl, cyclohexyl, cyclopentyl, phenyl or     mesityl; -   Y is a monoanionic ligand selected from the group consisting of H,     F, Cl, Br, OCOCH₃, OCOCF₃, OSO₂CF₃, CN and OH; -   X¹ is a substituent on an atom of the acridinyl unit or a     substituent on an atom of the quinolinyl unit,     -   where X¹ is selected from the group consisting of hydrogen, F,         Cl, Br, OH, NH₂, NO₂, —NC(O)R, C(O)NR₂, —OC(O)R, —C(O)OR, CN and         borane derivatives which can be obtained from the catalyst of         the formula (I) by reaction with NaBH₄ and unsubstituted         C₁-C₁₀-alkoxy, C₁-C₁₀-alkyl, C₃-C₁₀-cycloalkyl,         C₃-C₁₀-heterocyclyl comprising at least one heteroatom selected         from among N, O and S, C₅-C₁₀-aryl and C₅-C₁₀-heteroaryl         comprising at least one heteroatom selected from among N, O and         S; -   M is ruthenium or iridium.

In a further preferred embodiment, the process of the invention is carried out in the presence of at least one complex catalyst from the group consisting of the catalysts of the formulae (VI), (VII), (VIII), (IX), (X), (XI), (XII) and (XIII), where

-   R^(a) and R^(b) are each, independently of one another, methyl,     ethyl, isopropyl, tert-butyl, cyclohexyl, cyclopentyl, phenyl or     mesityl; -   Y is a monoanionic ligand selected from the group consisting of H,     F, Cl, Br, I, OCOCH₃, OCOCF₃, OSO₂CF₃, CN and OH; -   X¹ is hydrogen;     and -   M is ruthenium or iridium.

In a particularly preferred embodiment, L³ is carbon monoxide (CO).

In a particularly preferred embodiment, the process of the invention is carried out in the presence of a complex catalyst of the formula (XIVa):

In a very particularly preferred embodiment, the process of the invention is carried out in the presence of a complex catalyst of the formula (XIVb):

In a further particularly preferred embodiment, the process of the invention is carried out in the presence of at least one homogeneously dissolved complex catalyst of the formula (XV) in which R¹, R², R³, L² and L³ are as defined above.

Complex catalysts of the formula (XV) can be obtained by reacting catalysts of the formula (I) with sodium borohydride (NaBH₄). The reaction proceeds according to the general reaction equation:

In a further particularly preferred embodiment, the process of the invention is carried out in the presence of a complex catalyst of the formula (XVI):

The borane derivative of the formula XVI can be obtained according to the following reaction equation:

In a further embodiment, the process of the invention is carried out using at least one complex catalyst comprising at least one element selected from groups 8, 9 and 10 of the Periodic Table (IUPAC nomenclature) and also at least one phosphorus donor ligand of the general formula (XXI),

where

-   -   n is 0 or 1;     -   R²¹, R²², R²³, R²⁴, R²⁵, R²⁶ are each, independently of one         another, unsubstituted or at least monosubstituted C₁-C₁₀-alkyl,         C₁-C₄-alkyldiphenylphosphine (—C₁-C₄-alkyl-P(phenyl)₂),         C₃-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl comprising at least one         heteroatom selected from among N, O and S, C₅-C₁₄-aryl or         C₅-C₁₀-heteroaryl comprising at least one heteroatom selected         from among N, O and S,         -   where the substituents are selected from the group             consisting of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl;     -   A is         -   i) a bridging group selected from the group consisting of             unsubstituted or at least monosubstituted N, O, P,             C₁-C₆-alkane, C₃-C₁₀-cycloalkane, C₃-C₁₀-heterocycloalkane             comprising at least one heteroatom selected from among N, O             and S, C₅-C₁₄-aromatic and C₅-C₆-heteroaromatic comprising             at least one heteroatom selected from among N, O and S,         -   where the substituents are selected from the group             consisting of: C₁-C₄-alkyl, phenyl, F, Cl, Br, OH, OR²⁷,             NH₂, NHR²⁷ and N(R²⁷)₂,         -   where R²⁷ is selected from among C₁-C₁₀-alkyl and             C₅-C₁₀-aryl;         -   or         -   ii) a bridging group of the formula (XXII) or (XXIII):

-   -   -   m, q are each, independently of one another, 0, 1, 2, 3 or             4;         -   R²⁸, R²⁹ are selected independently from the group             consisting of C₁-C₁₀-alkyl, F, Cl, Br, OH, OR²⁷, NH₂, NHR²⁷             and N(R²⁷)₂,             -   where R²⁷ is selected from among C₁-C₁₀-alkyl and                 C₅-C₁₀-aryl;         -   X¹¹, X¹² are each, independently of one another, NH, O or S;         -   X¹³ is a bond, NH, NR³⁰, O, S or CR³¹R³²,         -   R³⁰ is unsubstituted or at least monosubstituted C₁-C₁₀             alkyl, C₃-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl comprising at             least one heteroatom selected from among N, O and S,             C₅-C₁₄-aryl or C₅-C₁₀-heteroaryl comprising at least one             heteroatom selected from among N, O and S,             -   where the substituents are selected from the group                 consisting of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl;         -   R³¹, R³² are each, independently of one another,             unsubstituted or at least monosubstituted C₁-C₁₀-alkyl,             C₁-C₁₀-alkoxy, C₃-C₁₀-cycloalkyl, C₃-C₁₀-cycloalkoxy,             C₃-C₁₀-heterocyclyl comprising at least one heteroatom             selected from among N, O and S, C₅-C₁₄-aryl, C₅-C₁₄-aryloxy             or C₅-C₁₀-heteroaryl comprising at least one heteroatom             selected from among N, O and S,             -   where the substituents are selected from the group                 consisting of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl;

    -   Y¹, Y², Y³, are each, independently of one another, a bond,         unsubstituted or at least monosubstituted methylene, ethylene,         trimethylene, tetramethylene, pentamethylene or hexamethylene,         -   where the substituents are selected from the group             consisting of: F, Cl, Br, OH, OR²⁷, CN, NH₂, NHR²⁷, N(R²⁷)₂             and C₁-C₁₀-alkyl,         -   where R²⁷ is selected from among C₁-C₁₀-alkyl and             C₅-C₁₀-aryl.

According to the invention, A is a bridging group. When A is selected from the group consisting of unsubstituted or at least monosubstituted C₁-C₆-alkane, C₃-C₁₀-cycloalkane, C₃-C₁₀-heterocycloalkane, C₅-C₁₄-aromatic and C₅-C₆-heteroaromatic and bridging groups of the formula (II) or (III), two hydrogen atoms of the bridging group are replaced by bonds to the adjacent substituents Y¹ and Y² when n=0. When n=1, three hydrogen atoms of the bridging group are replaced by three bonds to the adjacent substituents Y¹, Y² and Y³.

When A is P (phosphorus), the phosphorus forms two bonds to the adjacent substituents Y¹ and Y² and one bond to a substituent selected from the group consisting of C₁-C₄-alkyl and phenyl when n=0. When n=1, the phosphorus forms three bonds to the adjacent substituents Y¹, Y² and Y³.

When A is N (nitrogen), the nitrogen forms two bonds to the adjacent substituents Y¹ and Y² and one bond to a substituent selected from the group consisting of C₁-C₄-alkyl and phenyl when n=0. When n=1, the nitrogen forms three bonds to the adjacent substituents Y¹, Y² and Y³.

When A is O (oxygen), n=0. The oxygen forms two bonds to the adjacent substituents Y¹ and Y².

Preference is given to complex catalysts which comprise at least one element selected from among ruthenium and iridium.

In a preferred embodiment, the process of the invention is carried out in the presence of at least one complex catalyst comprising at least one element selected from groups 8, 9 and 10 of the Periodic Table and also at least one phosphorus donor ligand of the general formula (XXI), where

-   -   n is 0 or 1;     -   R²¹, R²², R²³, R²⁴, R²⁵, R²⁶ are each, independently of one         another, unsubstituted C₁-C₁₀-alkyl, C₃-C₁₀-cycloalkyl,         C₃-C₁₀-heterocyclyl comprising at least one heteroatom selected         from among N, O and S, C₅-C₁₄-aryl or C₅-C₁₀-heteroaryl         comprising at least one heteroatom selected from among N, O and         S;     -   A is         -   i) a bridging group selected from the group consisting of             unsubstituted C₁-C₆-alkane, C₃-C₁₀-cycloalkane,             C₃-C₁₀-heterocycloalkane comprising at least one heteroatom             selected from among N, O and S, C₅-C₁₄-aromatic and             C₅-C₆-heteroaromatic comprising at least one heteroatom             selected from among N, O and S;         -   or         -   ii) a bridging group of the formula (XXII) or (XXIII):

-   -   -   m, q are each, independently of one another, 0, 1, 2, 3 or             4;         -   R²⁸, R²⁹ are selected independently from the group             consisting of C₁-C₁₀-alkyl, F, Cl, Br, OH, OR²⁷, NH₂, NHR²⁷             and N(R²⁷)₂,             -   where R²⁷ is selected from among C₁-C₁₀-alkyl and                 C₅-C₁₀-aryl;         -   X¹¹, X¹² are each, independently of one another, NH, O or S;         -   X¹³ is a bond, NH, NR³⁰, O, S or CR³¹R³²;         -   R³⁰ is unsubstituted C₁-C₁₀-alkyl, C₃-C₁₀-cycloalkyl,             C₃-C₁₀-heterocyclyl comprising at least one heteroatom             selected from among N, O and S, C₅-C₁₄-aryl or             C₅-C₁₀-heteroaryl comprising at least one heteroatom             selected from among N, O and S;         -   R³¹, R³² are each, independently of one another,             unsubstituted C₁-C₁₀-alkyl, C₁-C₁₀-alkoxy,             C₃-C₁₀-cycloalkyl, C₃-C₁₀-cycloalkoxy, C₃-C₁₀-heterocyclyl             comprising at least one heteroatom selected from among N, O             and S, C₅-C₁₄-aryl, C₅-C₁₄-aryloxy or C₅-C₁₀-heteroaryl             comprising at least one heteroatom selected from among N, O             and S;

    -   Y¹, Y², Y³, are each, independently of one another, a bond,         unsubstituted methylene, ethylene, trimethylene, tetramethylene,         pentamethylene or hexamethylene.

In a further preferred embodiment, the process of the invention is carried out in the presence of at least one complex catalyst comprising at least one element selected from groups 8, 9 and 10 of the Periodic Table and also at least one phosphorus donor ligand of the general formula (XXV),

where

-   -   R²¹, R²², R²³, R²⁴ are each, independently of one another,         unsubstituted or at least monosubstituted C₁-C₁₀-alkyl,         C₁-C₄-alkyldiphenylphosphine (—C₁-C₄-alkyl-P(phenyl)₂),         C₃-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl comprising at least one         heteroatom selected from among N, O and S, C₅-C₁₄-aryl or         C₅-C₁₀-heteroaryl comprising at least one heteroatom selected         from among N, O and S,         -   where the substituents are selected from the group             consisting of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl;     -   A is         -   i) a bridging group selected from the group consisting of             unsubstituted or at least monosubstituted N, O, P,             C₁-C₆-alkane, C₃-C₁₀-cycloalkane, C₃-C₁₀-heterocycloalkane             comprising at least one heteroatom selected from among N, O             and S, C₅-C₁₄-aromatic and C₅-C₆-heteroaromatic comprising             at least one heteroatom selected from among N, O and S,         -   where the substituents are selected from the group             consisting of: C₁-C₄-alkyl, phenyl, F, Cl, Br, OH, OR²⁷,             NH₂, NHR²⁷ or N(R²⁷)₂,         -   where R²⁷ is selected from among C₁-C₁₀-alkyl and             C₅-C₁₀-aryl;         -   or         -   ii) a bridging group of the formula (XXII) or (XXIII):

-   -   -   m, q are each, independently of one another, 0, 1, 2, 3 or             4;         -   R²⁸, R²⁹ are selected independently from the group             consisting of C₁-C₁₀-alkyl, F, Cl, Br, OH, OR²⁷, NH₂, NHR²⁷             and N(R²⁷)₂,             -   where R²⁷ is selected from among C₁-C₁₀-alkyl and                 C₅-C₁₀-aryl;         -   X¹¹, X¹² are each, independently of one another, NH, O or S,         -   X¹³ is a bond, NH, NR³⁰, O, S or CR³¹R³²;         -   R³⁰ is unsubstituted or at least monosubstituted             C₃-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl comprising at least             one heteroatom selected from among N, O and S, C₅-C₁₄-aryl             or C₅-C₁₀-heteroaryl comprising at least one heteroatom             selected from among N, O and S,             -   where the substituents are selected from the group                 consisting of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl;         -   R³¹, R³² are each, independently of one another,             unsubstituted or at least monosubstituted C₁-C₁₀-alkyl,             C₁-C₁₀-alkoxy, C₃-C₁₀-cycloalkyl, C₃-C₁₀-cycloalkoxy,             C₃-C₁₀-heterocyclyl comprising at least one heteroatom             selected from among N, O and S, C₅-C₁₄-aryl, C₅-C₁₄-aryloxy             or C₅-C₁₀-heteroaryl comprising at least one heteroatom             selected from among N, O and S,             -   where the substituents are selected from the group                 consisting of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl;

    -   Y¹, Y² are each, independently of one another, a bond,         unsubstituted or at least monosubstituted methylene, ethylene,         trimethylene, tetramethylene, pentamethylene or hexamethylene,         -   where the substituents are selected from the group             consisting of: F, Cl, Br, OH, OR²⁷, CN, NH₂, NHR²⁷, N(R²⁷)₂             and C₁-C₁₀-alkyl,         -   where R²⁷ is selected from among C₁-C₁₀-alkyl and             C₅-C₁₀-aryl.

In a further preferred embodiment, the process of the invention is carried out in the presence of at least one complex catalyst comprising at least one element selected from groups 8, 9 and 10 of the Periodic Table and also at least one phosphorus donor ligand of the general formula (XXVI),

where

-   -   R²¹, R²², R²³, R²⁴, R²⁵, R²⁶ are each, independently of one         another, unsubstituted or at least monosubstituted C₁-C₁₀-alkyl,         C₁-C₄-alkyldiphenylphosphine, C₃-C₁₀-cycloalkyl,         C₃-C₁₀-heterocyclyl comprising at least one heteroatom selected         from among N, O and S, C₅-C₁₄-aryl or C₅-C₁₀-heteroaryl         comprising at least one heteroatom selected from among N, O and         S,         -   where the substituents are selected from the group             consisting of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl;     -   A is a bridging group selected from the group consisting of         unsubstituted or at least monosubstituted N, P, C₁-C₆-alkane,         C₃-C₁₀-cycloalkane, C₃-C₁₀-heterocycloalkane comprising at least         one heteroatom selected from among N, O and S, C₅-C₁₄-aromatic         and C₅-C₆-heteroaromatic comprising at least one heteroatom         selected from among N, O and S,         -   where the substituents are selected from the group             consisting of: C₁-C₄-alkyl, phenyl, F, Cl, Br, OH, OR²⁷,             NH₂, NHR²⁷ and N(R²⁷)₂,         -   where R²⁷ is selected from among C₁-C₁₀-alkyl and             C₅-C₁₀-aryl;     -   Y¹, Y², Y³ are each, independently of one another, a bond,         unsubstituted or at least monosubstituted methylene, ethylene,         trimethylene, tetramethylene, pentamethylene or hexamethylene,         -   where the substituents are selected from the group             consisting of: F, Cl, Br, OH, OR²⁷, CN, NH₂, NHR²⁷, N(R²⁷)₂             and C₁-C₁₀-alkyl,         -   where R²⁷ is selected from among C₁-C₁₀-alkyl and             C₅-C₁₀-aryl.

In a further preferred embodiment, the process of the invention is carried out in the presence of at least one complex catalyst comprising at least one element selected from groups 8, 9 and 10 of the Periodic Table and also at least one phosphorus donor ligand of the general formula (XXV), where

-   -   R²¹, R²², R²³, R²⁴ are each, independently of one another,         methyl, ethyl, isopropyl, tert-butyl, cyclopentyl, cyclohexyl,         phenyl, or mesityl;     -   A is         -   i) a bridging group selected from the group consisting of             methane, ethane, propane, butane, cyclohexane, benzene,             naphthalene and anthracene;         -   or         -   ii) a bridging group of the formula (XXVII) or (XXVIII):

-   -   -   X¹¹, X¹² are each, independently of one another, NH, O or S;         -   X¹³ is a bond, NH, O, S or CR³¹R³²;         -   R³¹, R³² are each, independently of one another,             unsubstituted C₁-C₁₀-alkyl;

    -   Y¹, Y² are each, independently of one another, a bond, methylene         or ethylene.

In a particularly preferred embodiment, the process of the invention is carried out in the presence of at least one complex catalyst comprising at least one element selected from groups 8, 9 and 10 of the Periodic Table and also at least one phosphorus donor ligand of the general formula (XXIX) or (XXX),

where the abovementioned definitions and preferences apply to m, q, R²¹, R²², R²³, R²⁴, R²⁸, R²⁹, X¹⁹, X¹² and X¹³.

In a further particularly preferred embodiment, the process of the invention is carried out in the presence of at least one complex catalyst comprising at least one element selected from the group consisting of ruthenium and iridium and also at least one phosphorus donor ligand selected from the group consisting of 1,2-bis(diphenylphosphino)ethane (dppe), 1,3-bis(diphenylphosphino)propane (dppp), 1,4-bis(diphenylphosphino)butane (dppb), 2,3-bis(dicyclohexylphosphino)ethane (dcpe), 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (xantphos), 1,1,1-tris(diethylphosphinomethyl)ethane (rhodaphos), bis(2-diphenylphosphinoethyl)phenylphosphine and 1,1,1-tris(diphenylphosphinomethyl)-ethane (triphos).

In a further particularly preferred embodiment, the process of the invention is carried out in the presence of a complex catalyst comprising ruthenium and also at least one phosphorus donor ligand selected from the group consisting of 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (xantphos), bis(2-diphenylphosphino-ethyl)phenylphosphine and 1,1,1-tris(diphenylphosphinomethyl)ethane (triphos).

In a further particularly preferred embodiment, the process of the invention is carried out in the presence of a complex catalyst comprising iridium and also at least one phosphorus donor ligand selected from the group consisting of 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (xantphos), bis(2-diphenylphosphino-ethyl)phenylphosphine and 1,1,1-tris(diphenylphosphinomethyl)ethane (triphos).

For the purposes of the present invention, the term C₁-C₁₀-alkyl refers to branched, unbranched, saturated and unsaturated groups. Preference is given to alkyl groups having from 1 to 6 carbon atoms (C₁-C₆-alkyl). Greater preference is given to alkyl groups having from 1 to 4 carbon atoms (C₁-C₄-alkyl).

Examples of saturated alkyl groups are methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, amyl and hexyl.

Examples of unsaturated alkyl groups (alkenyl, alkynyl) are vinyl, allyl, butenyl, ethynyl and propynyl.

The C₁-C₁₀-alkyl group can be unsubstituted or substituted by one or more substituents selected from the group consisting of F, Cl, Br, hydroxy (OH), C₁-C₁₀-alkoxy, C₅-C₁₀-aryloxy, C₅-C₁₀-alkylaryloxy, C₅-C₁₀-heteroaryloxy comprising at least one heteroatom selected from among N, O, S, oxo, C₃-C₁₀-cycloalkyl, phenyl, C₅-C₁₀-heteroaryl comprising at least one heteroatom selected from among N, O, S, C₅-C₁₀-heterocyclyl comprising at least one heteroatom selected from among N, O, S, naphthyl, amino, C₁-C₁₀-alkylamino, C₅-C₁₀-arylamino, C₅-C₁₀-heteroarylamino comprising at least one heteroatom selected from among N, O, S, C₁-C₁₀-dialkylamino, C₁₀-C₁₂-diarylamino, C₁₀-C₂₀-alkylarylamino, C₁-C₁₀-acyl, C₁-C₁₀-acyloxy, NO₂, C₁-C₁₀-carboxy, carbamoyl, carboxamide, cyano, sulfonyl, sulfonylamino, sulfinyl, sulfinylamino, thiol, alkylthiol, C₅-C₁₀-arylthiol and C₁-C₁₀-alkylsulfonyl.

The above definition of C₁-C₁₀-alkyl applies analogously to C₁-C₃₀-alkyl and to C₁-C₆-alkane.

For the present purposes, the term C₃-C₁₀-cycloalkyl refers to saturated, unsaturated monocyclic and polycyclic groups. Examples of C₃-C₁₀-cycloalkyl are cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl or cycloheptyl. The cycloalkyl groups can be unsubstituted or substituted by one or more substituents as have been defined above for the C₁-C₁₀-alkyl group.

The abovementioned definition of C₃-C₁₀-cycloalkyl applies analogously to C₃-C₁₀-cycloalkane.

Alcohol Amination

The homogeneous catalysts can be produced either directly in their active form or only under the reaction conditions from customary precursors with addition of the appropriate ligands. Customary precursors are, for example, [Ru(p-cymene)Cl₂]₂, [Ru(benzene)Cl₂]_(n), [Ru(CO)₂Cl₂]_(n), [Ru(CO)₃Cl₂]₂ [Ru(COD)(allyl)], [RuCl₃*H₂O], [Ru(acetylacetonate)₃], [Ru(DMSO)₄Cl₂], [Ru(PPh₃)₃(CO)(H)Cl], [Ru(PPh₃)₃(CO)Cl₂], [Ru(PPh₃)₃(CO)(H)₂], [Ru(PPh₃)₃Cl₂], [Ru(cyclopentadienyl)(PPh₃)₂Cl], [Ru(cyclopentadienyl)(CO)₂Cl], [Ru(cyclopentadienyl)(CO)₂H], [Ru(cyclopentadienyl)(CO)₂]₂, [Ru(pentamethylcyclopentadienyl)(CO)₂]₂, [Ru(penta-methylcylcopentadienyl)(CO)₂H], [Ru(pentamethylcyclopentadienyl)(CO)₂]₂, [Ru(indenyl)(CO)₂Cl], [Ru(indenyl)(CO)₂H], [Ru(indenyl)(CO)₂]₂, ruthenocene, [Ru(binap)Cl₂], [Ru(bipyridine)₂Cl₂*2H₂O], [Ru(COD)Cl₂]₂, [Ru(pentamethylcyclopentadienyl)(COD)Cl], [Ru₃(CO)₁₂], [Ru(tetraphenylhydroxycyclopentadienyl)(CO)₂H], [Ru(PMe₃)₄(H)₂], [Ru(PEt₃)₄(H)₂], [Ru(PnPr₃)₄(H)₂], [Ru(PnBu₃)₄(H)₂], [Ru(PnOctyl₃)₄(H)₂], [IrCl₃*H₂O], KIrCl₄, K₃IrCl₆, [Ir(COD)Cl]₂, [Ir(cyclooctene)₂Cl]₂, [Ir(ethene)₂C1]₂, [Ir(cyclopentadienyl)Cl₂]₂, [Ir(pentamethylcyclopentadienyl)Cl₂]₂, [Ir(cylopentadienyl)(CO)₂], [Ir(pentamethylcyclopentadienyl)(CO)₂], [Ir(PPh₃)₂(CO)(H)], [Ir(PPh₃)₂(CO)(Cl)], [Ir(PPh₃)₃(Cl)].

For the purposes of the present invention, homogeneously catalyzed means that the catalytically active part of the complex catalyst is at least partly present in solution in the liquid reaction medium. In a preferred embodiment, at least 90% of the complex catalyst used in the process is present in solution in the liquid reaction medium, more preferably at least 95%, particularly preferably more than 99%; the complex catalyst is most preferably entirely present in solution in the liquid reaction medium (100%), in each case based on the total amount in the liquid reaction medium.

The amount of the metal component of the catalyst, preferably ruthenium or iridium, is generally from 0.1 to 5000 ppm by weight, in each case based on the total liquid reaction medium.

The reaction occurs in the liquid phase, generally at a temperature of from 20 to 250° C. The process of the invention is preferably carried out at temperatures in the range from 100° C. to 200° C., particularly preferably in the range from 110 to 160° C.

The reaction can generally be carried out at a total pressure of from 0.1 to 20 MPa absolute, which can be either the autogenous pressure of the solvent at the reaction temperature or the pressure of a gas such as nitrogen, argon or hydrogen. The process of the invention is preferably carried out at a total pressure in the range from 0.2 to 15 MPa absolute, particularly preferably at a total pressure in the range from 1 to 15 MPa absolute.

The average reaction time is generally from 15 minutes to 100 hours.

The aminating agent (ammonia) can be used in stoichiometric, substoichiometric or superstoichiometric amounts based on the hydroxyl groups to be aminated.

In a preferred embodiment, ammonia is used in a from 1- to 250-fold, preferably a from 1- to 100-fold, in particular in a from 1.5- to 10-fold, molar excess per mole of hydroxyl groups to be reacted in the starting material. Higher excesses of ammonia are also possible. The ammonia can be introduced in gaseous form, liquid form or as a solution in the solvent or starting material.

The process of the invention can be carried out either in a solvent or without solvent. Suitable solvents are polar and nonpolar solvents which can be used in pure form or in mixtures. For example, it is possible to use only one nonpolar or one polar solvent in the process of the invention. It is also possible to use mixtures of two or more polar solvents or mixtures of two or more nonpolar solvents or mixtures of one or more polar solvents with one or more nonpolar solvents. The product can also be used as solvent, either in pure form or in mixtures with polar or nonpolar solvents.

Suitable nonpolar solvents are, for example, saturated and unsaturated hydrocarbons such as hexane, heptane, octane, cyclohexane, benzene, toluene, xylene and mesitylene and linear and cyclic ethers such as THF, diethyl ether, 1,4-dioxane, MTBE (tert-butyl methyl ether), diglyme and 1,2-dimethoxyethane. Preference is given to using toluene, xylene or mesitylene.

Suitable polar solvents are, for example, water, dimethylformamide, formamide, tert-amylalcohol and acetonitrile. Preference is given to using water. The water can either be added before the reaction, be formed as water of reaction during the reaction or be added after the reaction in addition to the water of reaction. A further preferred solvent is tert-amylalcohol.

To carry out the reaction in the liquid phase, ammonia, the diol optionally together with one or more solvents, together with the complex catalyst are introduced into a reactor. The introduction of ammonia, diol, optionally solvent and complex catalyst can be carried out simultaneously or separately. The reaction can be carried out continuously, in the semibatch mode, in the batch mode, admixed in product as solvent or without admixing in a single pass.

It is in principle possible to use all reactors which are basically suitable for gas/liquid reactions at the given temperature and the given pressure for the process of the invention. Suitable standard reactors for gas/liquid reaction systems and for liquid/liquid reaction systems are, for example, indicated in K. D. Henkel, “Reactor Types and Their Industrial Applications”, in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH Verlag GmbH & Co. KGaA, DOI: 10.1002/14356007.b04_(—)087, chapter 3.3 “Reactors for gas-liquid reactions”. Examples which may be mentioned are stirred tank reactors, tube reactors or bubble column reactors.

In the amination reaction, a hydroxyl group, preferably a primary hydroxyl group (—CH₂—OH), of the starting material is reacted with ammonia to form a primary amino group (—NH₂), with in each case one mole of water of reaction being formed per mole of reacted hydroxyl group.

The reaction of 1,2-ethylene glycol leads, for example, to the corresponding 2-aminoethanol.

The reaction output formed in the reaction generally comprises the corresponding alkanolamines, the one or more solvents if used, the complex catalyst, possibly unreacted starting materials and ammonia and also the water of reaction formed.

Any excess ammonia present, any solvent present, the complex catalyst and the water of reaction are removed from the reaction output. The amination product obtained can be worked up further. The excess ammonia, the complex catalyst, any solvent or solvents and any unreacted starting materials can be recirculated to the amination reaction.

If the amination reaction is carried out without solvent, the homogeneous complex catalyst is dissolved in the product after the reaction. This can remain in the product or be separated off therefrom by a suitable method. Possibilities for separating off the catalyst are, for example, scrubbing with a solvent which is not miscible with the product and in which the catalyst dissolves better than in the product as a result of a suitable choice of the ligands. The catalyst concentration in the product is optionally reduced by multistage extraction. As extractant, preference is given to using a solvent which is also suitable for the target reaction, e.g. toluene, benzene, xylenes, alkanes such as hexanes, heptanes and octanes and acyclic or cyclic ethers such as diethyl ether and tetrahydrofuran, which can after concentration by evaporation be reused together with the extracted catalyst for the reaction. It is also possible to remove the catalyst by means of a suitable absorbent. The catalyst can also be separated off by adding water to the product phase if the reaction is carried out in a solvent which is immiscible with water. If the catalyst in this case dissolves preferentially in the solvent, it can be separated off with the solvent from the aqueous product phase and optionally be reused. This can be brought about by selection of suitable ligands. The resulting aqueous diamines, triamines or polyamines can be used directly as technical-grade amine solutions. It is also possible to separate the amination product from the catalyst by distillation.

If the reaction is carried out in a solvent, the latter can be miscible with the amination product and be separated off by distillation after the reaction. It is also possible to use solvents which have a miscibility gap with the amination products or the starting materials. Suitable solvents for this purpose are, for example, toluene, benzene, xylenes, alkanes such as hexanes, heptanes and octanes and acyclic or cyclic ethers such as diethyl ether, tetrahydrofuran and dioxane. As a result of suitable choice of the phosphine ligands, the catalyst preferentially dissolves in the solvent phase. The phosphine ligands can also be selected so that the catalyst dissolves in the amination product. In this case, the amination product can be separated from the catalyst by distillation.

The solvent can also be miscible with the starting materials and the product under the reaction conditions and only form a second liquid phase comprising the major part of the catalyst after cooling. As solvents which display this property, mention may be made by way of example of toluene, benzene, xylenes, alkanes such as hexanes, heptanes and octanes. The catalyst can then be separated off together with the solvent and be reused. The product phase can also be admixed with water in this variant. The proportion of the catalyst comprised in the product can subsequently be separated off by means of suitable absorbents such as polyacrylic acid and salts thereof, sulfonated polystyrenes and salts thereof, activated carbons, montmorillonites, bentonites and zeolites or else be left in the product.

The amination reaction can also be carried out in a two-phase system. In the case of the two-phase reaction, suitable nonpolar solvents are, in particular, toluene, benzene, xylenes, alkanes such as hexanes, heptanes and octanes in combination with lipophilic phosphine ligands on the transition metal catalyst, as a result of which the transition metal catalyst accumulates in the nonpolar phase. In this embodiment, in which the product and the water of reaction and any unreacted starting materials form a second phase enriched with these compounds the major part of the catalyst can be separated off from the product phase by simple phase separation and be reused.

If volatile by-products or unreacted starting materials or the water formed in the reaction or added after the reaction to aid the extraction are undesirable, they can be separated off from the product without problems by distillation.

It can also be advantageous for the water formed in the reaction to be removed continuously from the reaction mixture. The water of reaction can be separated off from the reaction mixture directly by distillation or as azeotrope with addition of a suitable solvent (entrainer) and using a water separator or be removed by addition of water-withdrawing auxiliaries.

The addition of bases can have a positive effect on product formation. Suitable bases which may be mentioned here are alkali metal hydroxides, alkaline earth metal hydroxides, alkaline metal alkoxides, alkaline earth metal alkoxides, alkali metal carbonates and alkaline earth metal carbonates, which can be used in amounts of from 0.01 to 100 molar equivalents based on the metal catalyst used.

The present invention further provides for the use of a complex catalyst comprising at least one element selected from groups 8, 9 and 10 of the Periodic Table and also at least one donor ligand for the homogeneously catalyzed preparation of alkanolamines which have a primary amino group (—NH₂) and a hydroxyl group (—OH) by alcohol amination of diols having two hydroxyl groups (—OH) by means of ammonia.

In a preferred embodiment, the present invention provides for the use of a homogeneously dissolved complex catalyst of the general formula (I):

where

-   -   L¹ and L² are each, independently of one another, PR^(a)R^(b),         NR^(a)R^(b), sulfide, SH, S(═O)R, C₅-C₁₀-heteroaryl comprising         at least one heteroatom selected from among N, O and S,         AsR^(a)R^(b), SbR^(a)R^(b) and N-heterocyclic carbenes of the         formula (II) or (III):

-   -   L³ is a monodentate two-electron donor selected from the group         consisting of CO, PR^(a)R^(b)R^(c), NO⁺, AsR^(a)R^(b)R^(c),         SbR^(a)R^(b)R^(c), SR^(a)R^(b), RCN, RNC, N₂, PF₃, CS, pyridine,         thiophene, tetrahydrothiophene and N-heterocyclic carbenes of         the formula (II) or (III);     -   R¹ and R² are both hydrogen or together with the carbon atoms to         which they are bound form a phenyl ring which together with the         quinolinyl unit of the formula (I) forms an acridinyl unit;     -   R, R^(a), R^(b), R^(c), R³, R⁴, and R⁵ are each, independently         of one another, unsubstituted or at least monosubstituted         C₃-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl comprising at least one         heteroatom selected from among N, O and S, C₅-C₁₀-aryl or         C₅-C₁₀-heteroaryl comprising at least one heteroatom selected         from among N, O and S,         -   where the substituents are selected from the group             consisting of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl;     -   Y is a monoanionic ligand selected from the group consisting of         H, F, Cl, Br, I, OCOR, OCOCF₃, OSO₂R, OSO₂CF₃, CN, OH, OR and         N(R)₂ or an uncharged molecule selected from the group         consisting of NH₃, N(R)₃ and R₂NSO₂R;     -   X¹ represents one, two, three, four, five, six or seven         substituents on one or more atoms of the acridinyl unit or one,         two, three, four or five substituents on one or more atoms of         the quinolinyl unit,         -   where the radicals X¹ are selected independently from the             group consisting of hydrogen, F, Cl, Br, I, OH, NH₂, NO₂,             —NC(O)R, C(O)NR₂, —OC(O)R, —C(O)OR, CN and borane             derivatives which can be obtained from the catalyst of the             formula I by reaction with NaBH₄ and unsubstituted or at             least monosubstituted C₁-C₁₀-alkoxy, C₁-C₁₀-alkyl,             C₃-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl comprising at least             one heteroatom selected from among N, O and S, C₅-C₁₀-aryl             and C₅-C₁₀-heteroaryl comprising at least one heteroatom             selected from among N, O and S,         -   where the substituents are selected from the group             consisting of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl;     -   and     -   M is iron, cobalt, nickel, ruthenium, rhodium, palladium,         osmium, iridium or platinum,         for the homogeneously catalyzed preparation of alkanolamines         which have a primary amino group (—NH₂) and a hydroxyl group         (—OH) by alcohol amination of diols having two hydroxy groups         (—OH) by means of ammonia, where the definitions and preferences         described above for the process of the invention apply to the         catalyst of the general formula (I).

In a further preferred embodiment, the present invention relates to the use of a homogeneously dissolved complex catalyst of the general formula (XV):

where

-   -   L¹ and L² are each, independently of one another, PR^(a)R^(b),         NR^(a)R^(b), sulfide, SH, S(═O)R, C₅-C₁₀-heteroaryl comprising         at least one heteroatom selected from among N, O and S,         AsR^(a)R^(b), SbR^(a)R^(b) or N-heterocyclic carbenes of the         formula (II) or (III):

-   -   L³ is a monodentate two-electron donor selected from the group         consisting of CO, PR^(a)R^(b)R^(c), NO⁺, AsR^(a)R^(b)R^(c),         SbR^(a)R^(b)R^(c), SR^(a)R^(b), RCN, RNC, N₂, PF₃, CS, pyridine,         thiophene, tetrahydrothiophene and N-heterocyclic carbenes of         the formula (II) or (III);     -   R¹ and R² are both hydrogen or together with the carbon atoms to         which they are bound form a phenyl ring which together with the         quinolinyl unit of the formula (I) forms an acridinyl unit;     -   R, R^(a), R^(b), R^(c), R³, R⁴ and R⁵ are each, independently of         one another, unsubstituted or at least monosubstituted         C₁-C₁₀-alkyl, C₃-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl comprising         at least one heteroatom selected from among N, O and S,         C₅-C₁₀-aryl or C₅-C₁₀-heteroaryl comprising at least one         heteroatom selected from among N, O and S,         -   where the substituents are selected from the group             consisting of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl;     -   Y is a monoanionic ligand selected from the group consisting of         H, F, Cl, Br, I, OCOR, OCOCF₃, OSO₂R, OSO₂CF₃, CN, OH, OR and         N(R)₂ or uncharged molecules selected from the group consisting         of NH₃, N(R)₃ and R₂NSO₂R;     -   X¹ represents one, two, three, four, five, six or seven         substituents on one or more atoms of the acridinyl unit or one,         two, three, four or five substituents on one or more atoms of         the quinolinyl unit,         -   where the radicals X¹ are selected independently from the             group consisting of hydrogen, F, Cl, Br, I, OH, NH₂, NO₂,             —NC(O)R, C(O)NR₂, —OC(O)R, —C(O)OR, CN and borane             derivatives which can be obtained from the catalyst of the             formula I by reaction with NaBH₄ and unsubstituted or at             least monosubstituted C₁-C₁₀-alkoxy, C₁-C₁₀-alkyl,             C₃-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl comprising at least             one heteroatom selected from among N, O and S, C₅-C₁₀-aryl             and C₅-C₁₀-heteroaryl comprising at least one heteroatom             selected from among N, O and S,         -   where the substituents are selected from the group             consisting of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl;     -   and     -   M is iron, cobalt, nickel, ruthenium, rhodium, palladium,         osmium, iridium or platinum,         for the homogeneously catalyzed preparation of alkanolamines         which have a primary amino group (—NH₂) and a hydroxyl group         (—OH) by alcohol amination of diols having two hydroxyl groups         (—OH) by means of ammonia, where the definitions and preferences         described above for the process of the invention apply to the         catalyst of the general formula (XV).

The present invention further provides for the use of a complex catalyst comprising at least one element selected from groups 8, 9 and 10 of the Periodic Table and also at least one phosphorus donor ligand of the general formula (XXI),

where

-   -   n is 0 or 1;     -   R²¹, R²², R²³, R²⁴, R²⁵, R²⁶ are each, independently of one         another, unsubstituted or at least monosubstituted C₁-C₁₀-alkyl,         C₁-C₄-alkyldiphenylphosphine (—C₁-C₄-alkyl-P(phenyl)₂),         C₃-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl comprising at least one         heteroatom selected from among N, O and S, C₅-C₁₄-aryl or         C₅-C₁₀-heteroaryl comprising at least one heteroatom selected         from among N, O and S,         -   where the substituents are selected from the group             consisting of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl;     -   A is         -   i) a bridging group selected from the group consisting of             unsubstituted or at least monosubstituted N, O, P,             C₁-C₆-alkane, C₃-C₁₀-cycloalkane, C₃-C₁₀-heterocycloalkane             comprising at least one heteroatom selected from among N, O             and S, C₅-C₁₄-aromatic and C₅-C₆-heteroaromatic comprising             at least one heteroatom selected from among N, O and S,         -   where the substituents are selected from the group             consisting of: C₁-C₄-alkyl, phenyl, F, Cl, Br, OH, OR²⁷,             NH₂, NHR²⁷ or N(R²⁷)₂,         -   where R²⁷ is selected from among C₁-C₁₀-alkyl and             C₅-C₁₀-aryl;         -   or         -   ii) a bridging group of the formula (XXII) and (XXIII):

-   -   -   m, q are each, independently of one another, 0, 1, 2, 3 or             4;         -   R²⁸, R²⁹ are selected independently from the group             consisting of C₁-C₁₀-alkyl, F, Cl, Br, OH, OR²⁷, NH₂, NHR²⁷             and N(R²⁷)₂,             -   where R²⁷ is selected from among C₁-C₁₀-alkyl and                 C₅-C₁₀-aryl;         -   X¹¹, X¹² are each, independently of one another, NH, O or S;         -   X¹³ is a bond, NH, NR³⁰, O, S or CR³¹R³²,         -   R³⁰ is unsubstituted or at least monosubstituted             C₁-C₁₀-alkyl, C₃-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl             comprising at least one heteroatom selected from among N, O             and S, C₅-C₁₄-aryl or C₅-C₁₀-heteroaryl comprising at least             one heteroatom selected from among N, O and S,             -   where the substituents are selected from the group                 consisting of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl;         -   R³¹, R³² are each, independently of one another,             unsubstituted or at least monosubstituted C₁-C₁₀-alkyl,             C₁-C₁₀-alkoxy, C₃-C₁₀-cycloalkyl, C₃-C₁₀-cycloalkoxy,             C₃-C₁₀-heterocyclyl comprising at least one heteroatom             selected from among N, O and S, C₅-C₁₄-aryl, C₅-C₁₄-aryloxy             or C₅-C₁₀-heteroaryl comprising at least one heteroatom             selected from among N, O and S,             -   where the substituents are selected from the group                 consisting of: F, Cl, Br, OH, CN, NH₂ and C₁-C₁₀-alkyl;

    -   Y¹, Y², Y³ are each, independently of one another, a bond,         unsubstituted or at least monosubstituted methylene, ethylene,         trimethylene, tetramethylene, pentamethylene or hexamethylene,         -   where the substituents are selected from the group             consisting of: F, Cl, Br, OH, OR²⁷, CN, NH₂, NHR²⁷, N(R²⁷)₂             and C₁-C₁₀-alkyl,         -   where R²⁷ is selected from among C₁-C₁₀-alkyl and             C₅-C₁₀-aryl,             for the homogeneously catalyzed preparation of alkanolamines             which have a primary amino group and a hydroxyl group by             alcohol amination of diols having two hydroxyl groups (—OH)             by means of ammonia.

The definitions and preferences described for the process of the invention apply to the use of the complex catalyst of the formula (XXI) for the homogeneously catalyzed preparation of alkanolamines which have a primary amino group (—NH₂) and a hydroxyl group (—OH) by alcohol amination of diols having two hydroxyl groups (—OH) by means of ammonia.

The invention is illustrated by the following examples without being restricted thereto.

EXAMPLE

General method for the catalytic amination of alcohols by means of ammonia according to the invention

Ligand L, metal salt M or catalyst complex XIVb (for preparation, see below, weighed out under an inert atmosphere), solvent and the alcohol to be reacted were placed under an Ar atmosphere in a 160 ml Parr autoclave (stainless steel V4A) having a magnetically coupled inclined blade stirrer (stirring speed: 200-500 revolutions/minute). The indicated amount of ammonia was introduced at room temperature either in precondensed form or directly from the pressurized NH₃ gas bottle. If hydrogen was used, this was effected by iterative differential pressure metering. The steel autoclave was electrically heated to the temperature indicated and heated for the time indicated while stirring (500 revolutions/minute) (internal temperature measurement). After cooling to room temperature, venting the autoclave and outgassing the ammonia at atmospheric pressure, the reaction mixture was analyzed by GC (30 m RTX5 amine 0.32 mm 1.5 μm). The results for the amination of 1,4-butanediol (tables 1a, 1b and 2), diethylene glycol (tables 3a, 3b and 4), monoethylene glycol (table 5) and diethanolamine (table 6), 1,5-pentanediol, 1,9-nonanediol, 1,6-hexanediol and 1,10-decanediol (table 7) and 2,5-(dimethanol)-furan (table 8) are given below.

Synthesis of the Catalyst Complex XIVb

a) Synthesis of 4,5-bis(dicyclohexylphosphinomethyl)acridine

A solution of 4,5-bis(bromomethyl)acridine¹ (5.2 g, 14.2 mmol) and dicyclohexylphosphine (8.18 g, 36.8 mmol) in 65 ml of anhydrous, degassed methanol was heated at 50° C. under an inert argon atmosphere for 66 hours. After cooling to room temperature, triethylamine (5.72 g, 56.7 mmol) was added and the mixture was stirred for 1 hour. Evaporation of the solvent gave a whitish yellow solid in a red oil. Extraction by means of 3×40 ml of MTBE and concentration of the filtrate gave a reddish brown oil (¹H NMR: mixture of product & HPCy₂). Taking up in a little warm MTBE followed by addition of ice-cooled methanol resulted in precipitation of a yellow, microcrystalline solid. Oscillation and drying under reduced pressure gave air sensitive 4,5-bis(dicyclohexylphosphinomethyl)acridine (2.74 g, 33%) as a yellow powder.

¹H NMR (360.63 MHz, d8-toluene): δ [ppm]=8.07 (s, 1H, H9), 7.91 (d, J=8.3 Hz, 2H, Ar—H), 7.42 (d, J=8.3 Hz, 2H, Ar—H), 7.21 (dd, J=8.3 Hz, J=7.2 Hz, 2H, Ar—H), 3.89 (bs, 4H, —CH₂—P), 1.96-1.85 (m, 8H, Cy-H), 1.77-1.54 (m, 20H, Cy-H), 1.26-1.07 (m, 16H, Cy-H). ³¹P{¹H} NMR (145.98 MHz, d8-toluene): δ [ppm]=2.49 (s, —CH₂—P(Cy)₂).

b) Synthesis of the Catalyst Complex XIVb

4,5-bis(dicyclohexylphosphinomethyl)acridine (1855 mg, 3.1 mmol) and [RuHCl(CO)(PPh₃)₃]² (2678 mg, 2.81 mmol) were heated at 70° C. in 80 ml of degassed toluene for 2 hours. The resulting dark brown solution was evaporated to dryness, the residue was slurried in 3×20 ml of hexane and isolated by filtration. Drying under reduced pressure gave Ru-PNP Pincer complex XIVb (1603 mg, 75%) as an orange-brown powder. ¹H NMR (360.63 MHz, d8-toluene): δ [ppm]=8.06 (s, 1H, H9), 7.43 (d, J=7.6 Hz, 2H, Ar—H), 7.33 (d, J=6.5 Hz, 2H, Ar—H), 7.06-7.02 (m, 2H, Ar—H), 5.02 (d, J=11.9 Hz, 2H, —CHH—PCy₂), 3.54 (d, J=12.2 Hz, 2H, —CHH—PCy₂), 2.87 (bs, 2H, —P(C_(a)H(CH₂)₅)₂), 2.54 (bs, 2H, —P(C_(b)H(CH₂)₅)₂), 2.18 (bs, 2H, Cy-H), 1.88-1.85 (m, 8H, Cy-H), 1.65 (bs, 6H, Cy-H), 1.42-1.35 (m, 14H, Cy-H), 1.17-0.82 (m, 12H, Cy-H), −16.29 (t, J=19.1 Hz, 1H, Ru—H). ³¹P{¹H} NMR (145.98 MHz, d8-toluene): δ [ppm]=60.89 (s, —CH₂—P(Cy)₂).

-   [1] J. Chiron, J. P. Galy, Synlett, 2003, 15, 2349-2350. -   [2] Literature instructions: Inorganic Syntheses 1974, 15, 48. See     also: T. Joseph, S. S. Deshpande, S. B. Halligudi, A. Vinu, S.     Ernst, M. Hartmann, J. Mol. Cat. (A) 2003, 206, 13-21.

Ligand name CAS IUPAC Triphos 22031-12-5 1,1,1-tris(diphenylphosphinomethyl)ethane Xantphos 161265-03-8 4,5-bis(diphenylphosphino)-9,9- dimethylxanthene Rhodaphos 22031-14-7 1,1,1-tris(diethylposphinomethyl)ethane DPPEPP 23582-02-7 bis(2- diphenylphosphinoethyl)phenylphosphine Tetraphos 23582-03-8 tris[2-(diphenylphosphino)ethyl]phosphine dppb 7688-25-7 1,4-Bis(diethylphospino)butane

TABLE 1a Amination of 1,4-butanediol using various catalyst systems

Re- action Met. Lig. pres- [M] [L] Con- T Time NH₃ sure Metal salt (mol Ligand (mol ver- Selectivity^(c) No. Solvent^(a)) [° C.] [h] [eq.]^(e)) [bar] [M] %)^(f)) [L] %)^(f)) sion^(b) a:b:c 1 Toluene 155 12 6 49 [RuHCl(CO)(PPh₃)₃] 0.1 Triphos 0.1 74.7 59.1 0.7  6.7 2 Toluene 155 12 6  66^(d)) [RuHCl(CO)(PPh₃)₃] 0.1 Triphos 0.1 61.8 78.0 0.6  5.4 3 Toluene 155 12 6 45 [RuHCl(CO)(PPh₃)₃] 0.1 Xantphos 0.1 35.0 81.8 0.0  6.4 4 Toluene 155 12 6 47 [Ru(COD)methylallyl₂] 0.1 Tetraphos 0.1  6.0  8.5 0.0  1.6 5 Toluene 155 12 6 39 [RuHCl(CO)(PPh₃)₃] 0.2 Rhodaphos 0.2 39.8 17.5 0.0  4.6 6 Toluene 155 12 6 38 [RuHCl(CO)(PPh₃)₃] 0.2 DPPEPP 0.2 66.6 68.1 0.1 11.0 ^(a))50 ml of solvent; Batch size: 25 mmol of 1,4-butanediol ^(b)Evaluation by GC (% by area); ^(c)Product selectivity determined by GC; ^(d))Injected cold: 5 bar H₂, 8 bar NH₃, ^(e))Molar equivalents of NH₃ per OH function on the substrate; ^(f))mol % based on number of OH functions on the substrate

TABLE 1b Amination of 1,4-butanediol using various catalyst systems Reaction T NH₃ pressure Met. [M] Lig. [L] Selectivity^(c) No Solvent^(a)) [° C.] Time [h] [Eq.]^(d)) [bar] Metall salt [M] (mol %)e^(f)) Ligand [L] (mol %)^(e)) Conversion^(b) a: b: c 1 THF 155 12 6 40 [RuHCl(CO)(PPh₃)₃] 0.2 dppb 0.2 49.6 61.4 0.0 20.3 ^(a))50 ml of solvent; Batch size: 25 mmol of 1,4-butanediol; ^(b))Evaluation by GC (% by area); ^(c))Product selectivity determined by GC; ^(d))Molar equivalents of NH₃ per OH function on the substrate; ^(e))mol % based on number of OH functions on the substrate

TABLE 2 Amination of 1,4-butanediol using XIVb as catalyst system

Reaction T Time NH₃ pressure Selectivity No.^(a)) Solvent [° C.] [h] [eq.]^(e)) [bar] Further condition Conversion^(b) a b C 1 Toluene 155 12 6 42 54.6 72.2 8.8 17.7 2 Toluene 155 12 6 41 5.0 mol % of water 63.0 71.8 9.3 17.3 3 Toluene 155 12 6 55 5 bar of H₂ injected cold 25.0 81.0 4.8 13.6 4 Toluene 155 12 9 47 61.1 74.2 8.9 15.7 5 p-Xylene 155 12 6 44 70.6 62.6 5.8 28.7 6 p-Xylene 155 12 6 40 — 42.0 78.8 3.5 16.5 7 p-Xylene 155 12 9 48 62.3 72.3 7.6 18.5 8 p-Xylene 155 12 18  78 48.1 75.9 2.6 17.4 9 Mesitylene* 155 12 6 39 — 58.3 70.5 6.7 20.3 ^(a))Conditions unless indicated otherwise: 50 ml of solvent, batch size 25 mmol of 1,4-butanediol, 0.1 mol % of catalyst complex XIVb (based on number of OH functions on the substrate), ^(b)Evaluation by GC (% by area), ^(c))Product selectivity determined by GC, ^(e))Molar equivalents of NH₃ per OH function on the substrate

TABLE 3a Amination of diethylene glycol using various catalyst systems

Re- action Met. Lig. pres- [M] [L] Con- T Time NH₃ sure Metal salt (mol Ligand (mol ver- Selectivity^(c) No. Solvent^(a)) [° C.] [h] [eq.]^(e)) [bar] [M] %)^(f)) [L] %)^(f)) sion^(b) a:b:c 1 Toluene 155 12 6 49 [RuHCl(CO)(PPh₃)₃] 0.1 Triphos 0.1 51.0 66.2 0.9 5.9 2 Toluene 155 12 6  59^(d)) [RuHCl(CO)(PPh₃)₃] 0.1 Triphos 0.1 16.2 87.3 0.1 2.3 3 Toluene 180 12 6 43 [RuHCl(CO)(PPh₃)₃] 0.2 Xantphos 0.1 27.7 67.1 0.2 5.3 4 Toluene 155 12 6 44 [Ru(COD)methylallyl₂] 0.1 Tetraphos 0.1  3.9  0.0 0.0 1.1 5 Toluene 155 12 6 40 [RuHCl(CO)(PPh₃)₃] 0.2 Rhodaphos 0.2 21.8  4.7 0.0 1.3 ^(a))50 ml of solvent; Batch size: 25 mmol of diethylene glycol; ^(b)Evaluation by GC (% by area); ^(c)Product selectivity determined by GC; ^(d))Injected cold: 5 bar of H₂, 8 bar of NH₃; ^(e))Molar equivalents of NH₃ per OH function on the substrate; ^(f))mol % based on the number of OH functions on the substrate

TABLE 3b Amination of diethylene glycol using various catalyst systems

Re- action Met. Lig. pres- [M] [L] Con- T Time NH₃ sure Metal salt (mol Ligand (mol ver- Selectivity^(c) No. Solvent^(a)) [° C.] [h] [eq.]^(e)) [bar] [M] %)^(f)) [L] %)^(f)) sion^(b) a:b:c 1 Toluol 180 12 6  65^(d)) [RuHCl(CO)(PPh₃)₃] 0.2 Triphos 0.2 97.6 26.4 13.4 54.0 2 Toluol 155 12 6 40 [RuHCl(CO)(PPh₃)₃] 0.2 DPPEPP 0.2 21.5 46.0  0.0  2.3 ^(a))50 ml of solvent; Batch size: 25 mmol of diethylene glycol; ^(b)Evaluation by GC (% by area); ^(c)Product selectivity determined by GC; ^(d))Injected cold: 5 bar of H₂, 8 bar of NH₃; ^(e))Molar equivalents of NH₃ per OH function on the substrate; ^(f))mol % based on the number of OH functions on the substrate

TABLE 4 Amination of diethylene glycol using XIVb as catalyst system

Reaction T Time NH₃ pressure Selectivity^(c)) No.^(a)) Solvent [° C.] [h] [eq.]^(d)) [bar] Further conditions Conversion^(b)) a b c  1 Toluene 135 12 6 38 40.4 85.8  2.5 6.7  2 Toluene 135 12 6 38 0.2 mol % of KOtBu 11.7 69.8  3.4 5.0  3 Toluene 135 12 6 36 1 mol % of water 37.9 86.4  2.1 6.0  4 Toluene 135 12 6 37 42.1 87.1  3.3 6.5  5 Toluene 135 12 9 42 33.8 81.4  1.5 5.5  6 Toluene 135 12 18  57 36.5 78.4  2.9 9.4  7 Toluene 135 15   1.1  9 49.1 76.4  3.2 8.7  8 Toluene 135 24 6 37 60.9 75.8  9.3 8.3  9 Toluene 135 60 9 45 cat: 0.05 mol % 28.1 81.7  6.3 2.5 10 Toluene 155 12 6 40 5.0 mol % of water 74.8 57.2 18.5 11.1  11 Toluene 155 12 6 66 5 bar of H2 61.8 69.2 18.6 8.0 12 Toluene 155 12 9 63 5 bar of H2 + 55.5 72.7 16.0 6.8 1.0 mol % of water 13 Toluene 155 12 9 66 5 bar of H2 53.1 75.0 14.1 5.8 14 p-Xylene 155 12 6 48 74.4 65.8 11.5 9.5 15 p-Xylene 155 12 6 38 1.0 mol % of water 77.5 52.9 21.6 16.9  16 p-Xylene 155 24 6 53 1.0 mol % of water 84.6 51.8 20.8 12.9  17 p-Xylene 180 12 6 50 100.0   0.4 46.1 27.9  18 p-Xylene 180 12 6 50 5 mol % of H2O 100.0   0.4 48.2 27.4  ^(a))Conditions unless indicated otherwise: 50 ml of solvent, Batch size 25 mmol of diethylene glycol, 0.1 mol % of catalyst complex XIVb (based on number of OH functions on the substrate); b)Evaluation by GC (% by area); ^(c))Product selectivity determined by GC; ^(e))Molar equivalents of NH₃ per OH function on the substrate

TABLE 5 Amination of monoethylene glycol using XIVb as catalyst system

Reaction T Time NH₃ pressure Selectivity No.^(a)) Solvent [° C.] [h] [eq.]^(d)) [bar] Further conditions Conversion^(b) a b c 1 Toluene 135 12 6 35 14.0 68.6 16.6 0.5 2 Toluene 135 12 6 38 0.2 mol % of KOtBu 39.3 65.8 18.9 0.7 3 Toluene 135 12 9 44 11.0 71.9 17.5 0.7 4 Toluene 135 12 12  48 10.6 68.2 17.5 2.5 5 Toluene 135 12 18  54 13.7 69.0 15.6 2.7 6 p-Xylene 155  3 6 38 18.2 56.9 19.5 1.0 ^(a))Conditions unless indicated otherwise: 50 ml of solvent; Batch size 25 mmol of monoethylene glycol, 0.1 mol % of catalyst complex XIVb (based on number of OH functions on the substrate); ^(b)Evaluation by GC (% by area); ^(c))Product selectivity determined by GC; ^(d))Molar equivalents of NH₃ per OH function on the substrate

TABLE 6 Amination of diethanolamine using XIVb as catalyst system

Reaction T Time NH₃ pressure Selectivities No.^(a)) Solvent [° C.] [h] [eq.]^(d)) [bar] Further conditions Conversion^(b) a b c d 1 Toluene 135 12 9 43 22.7 51.9 0.4 0.0 31.2 2 Toluene 155 12 6 44 49.0 41.4 1.8 0.0 30.2 3 Toluene 155 24 6 42 69.0 32.6 2.1 0.0 30.6 4 Toluene 155 12 6 45 32.5 31.8 1.8 0.0 34.6 5 Toluene 155 12 9 54 57.5 47.4 2.5 4.1 34.3 6 Toluene 155 12 6 44 1 mol % of KOtBu 25.7 34.8 3.3 0.0 25.3 7 Toluene 155 12 12  57 50.8 39.8 1.3 3.0 36.6 8 Toluene 155 12 6 44 1 mol % of water 51.7 40.5 1.4 3.4 33.8 9 Toluene 155 12 6 43 5 mol % of water 50.6 42.2 1.4 4.6 30.8 10  Toluene 155 12 6 60 5 bar of H2 33.4 51.1 1.4 4.4 30.6 ^(a))Conditions unless indicated otherwise: 50 ml of solvent, Batch size 25 mmol of diethanolamine, 0.1 mol % of catalyst complex XIVb (based on number of OH functions on the substrate); ^(b)Evaluation by GC (% by area); ^(c))Product selectivity determined by GC; ^(d))Molar equivalents of NH₃ per OH function on the substrate

TABLE 7 Amination of (1,5-pentanediol, 1,6-hexanediol, 1,10-decanediol, 1,9-Nonanediol) using various catalyst systems

Re- action Met. Lig. pres- Solvent [M] [L] Con- T Time NH₃ sure (water- Metall salt (mol Ligand (mol ver- Selectivity^(c) No.^(a)) Substrate [° C.] [h] [eq.]^(e)) [bar] free [M] %)^(f)) [L] %)^(f)) sion^(b)) a:b 1 1,6-Hexa- 155 12 6 42 Toluol [RuHCl(CO)(PPh₃)₃] 0.10 Triphos 0.10 83.0 61.3 25.7 nediol 2 1,6-Hexa- 155 12 6 36 Toluol [RuHCl(CO)(PPh₃)₃] 0.10 Xantphos 0.10 33.4 84.9  4.6 nediol 3 1,6-Hexa- 155 12 6 40 Toluol [RuHCl(CO)(PPh₃)₃] 0.10 DPPEPP 0.10 70.7 66.5 16.0 nediol 4 1,6-Hexa- 155 12 6 44 Toluol [RuHCl(CO)(PPh₃)₃] 0.10 Rhodaphos 0.10 35.1 53.0  2.0 nediol 5 1,10-Deca- 155 24 6 39 Toluol [RuHCl(CO)(PPh₃)₃] 0.20 Triphos 0.20 85.7 43.0 44.4 nediol 7 1,5-Penta- 155 12 6 40 Toluol [RuHCl(CO)(PPh₃)₃] 0.10 Triphos 0.10 70.3 66.8  1.3 nediol 8 1,5-Penta- 155 12 6 45 Toluol [RuHCl(CO)(PPh₃)₃] 0.10 DPPEPP 0.10 50.9 64.6  7.1 nediol  9^(d)) 1,9-Nona- 155 24 12  14 Mesi- [RuHCl(CO)(PPh₃)₃] 0.20 Triphos 0.20 79.3 54.0 31.1 nediol tylene ^(a))50 ml of solvent; Batch size: 25 mmol of diol; ^(b))Evaluation by GC (% by area); ^(c)Product selectivity determined by GC (% by area); ^(d))Batch size: 50 mmol of substrate; Batch size: 50 mmol of diol; ^(e))Molar equivalents of NH₃ per OH function on the substrate; ^(f))mol % based on number of OH functions on the substrate

TABLE 8 Amination of 2,5-dimethanolfuran

Re- action Met. Lig. pres- Solvent [M] [L] Con- Selec- Sub- T Time konz. NH₃ sure (water- Metall salt (mol Ligand (mol ver- tivity^(c) No.^(a)) strate [° C.] [h] [mol/l] [eq.]^(d)) [bar] free [M] %)^(e)) [L] %)^(e)) sion^(b)) a:b 1 2,5-di- 140 24 1   6 15 THF [RuHCl(CO)(PPh₃)₃] 0.20 Triphos 0.20 46.8 63.1 10.2 methan- olfuran 2 2,5-di- 140  3 0.5 6 32 tert- XIVb 0.10 — — 84.6 49.2 43.6 methan- butanol olfuran ^(a))40 ml of solvent; Batch size: 40 mmol of diol; ^(b))Evaluation by GC (% by area); ^(c)Product selectivity determined by GC (% by area); ^(d))Molar equivalents of NH₃ per OH function on the substrate; ^(e))mol % based on number of OH functions on the substrate 

The invention claimed is:
 1. A process for preparing an alkanolamine comprising a primary amino group (—NH₂) and a hydroxyl group (—OH), the process comprising: aminating a diol comprising two functional groups of formula (—CH₉—OH) with ammonia, to eliminate water and obtain the alkanolamine, wherein the aminating is homogeneously catalyzed in the presence a complex catalyst comprising at least one element selected from groups consisting of 8, 9, and 10 of the Periodic Table, and a donor ligand, wherein the complex catalyst is a catalyst represented by formula (I):

wherein L¹ and L² are each independently PR^(a)R^(b), NR^(a)R^(b), sulfide, SH, S(═O)R, a C₅-C₁₀-heteroaryl comprising at least one heteroatom selected from the group consisting of N, O, and S, AsR^(a)R^(b), SbR^(a)R^(b), or an N-heterocyclic carbene of formula (II) or (III):

L³ is a monodentate two-electron donor selected from the group consisting of CO, PR^(a)R^(b)R^(c), NO⁺, AsR^(a)R^(b)R^(c), SbR^(a)R^(b)R^(c), SR^(a)R^(b), RCN, RNC, N₂, PF₃, CS, pyridine, thiophene, tetrahydrothiophene, and an N-heterocyclic carbene of formula (II) or (III); R¹ and R² are both hydrogen or together with the carbon atoms to which they are bound form a phenyl ring, which forms an acridinyl unit with the quinolinyl unit of the formula (I); R, R^(a), R^(b), R^(c), R³, R⁴ and R⁵ are each independently an unsubstituted or at least monosubstituted C₃-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl comprising at least one heteroatom selected from the group consisting of N, O, and S, C₅-C₁₀-aryl, or C₅-C₁₀-heteroaryl comprising at least one heteroatom selected from the group consisting of N, O, and S, wherein the substituents are selected from the group consisting of F, Cl, Br, OH, CN, NH₂, and a C₁-C₁₀-alkyl; Y is a monoanionic ligand selected from the group consisting of H, F, Cl, Br, I, OCOR, OCOCF₃, OSO₂R, OSO₂CF₃, CN, OH, OR, and N(R)₂, or an uncharged molecule selected from the group consisting of NH₃, N(R)₃, and R₂NSO₂R; X¹ is one to seven radical substituents on an atom of the acridinyl unit or one to five radical substituents on an atom of the quinolinyl unit, wherein the radicals are each independently selected from the group consisting of hydrogen, F, Cl, Br, I, OH, NH₂, NO₂, —NC(O)R, C(O)NR₂, —OC(O)R, —C(O)OR, CN, and a borane derivative obtained by reacting the catalyst of the formula (I) with NaBH₄ and an unsubstituted or at least monosubstituted C₁-C₁₀-alkoxy, C₁-C₁₀-alkyl, C₃-C₁₀-cycloalkyl, C₃-C₁₀-heterocyclyl comprising at least one a heteroatom selected from the group consisting of N, O, and S, C₅-C₁₀-aryl, and C₅-C₁₀-heteroaryl comprising at least one a heteroatom selected from the group consisting of N, O, and S, wherein the substituents are selected from the group consisting of F, Cl, Br, OH, CN, NH₇, and a C₁-C₁₀-alkyl; and M is iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium, or platinum.
 2. The process of claim 1, wherein R¹ and R² are both hydrogen and the complex catalyst is a catalyst of formula (IV):


3. The process of claim 1, wherein R¹ and R² together with the carbon atoms to which they are bound form a phenyl ring, which forms an acridinyl unit together with the quinolinyl units of the formula (I), and the complex catalyst is a catalyst has a formula (V):


4. The process of claim 1, wherein the complex catalyst is selected from the group of catalysts of having a formula selected form the group consisting of formulae (VI), (VII), (VIII), (IX), (X), (XI), (XII), and (XIII):


5. The process of claim 1, wherein the complex catalyst is a catalyst of formula (XIVb):


6. The process of claim 1, wherein, in formula (I), Y is F, Cl, or Br.
 7. The process of claim 1, wherein, in formula (I), L³ is CO.
 8. The process of claim 1, wherein the aminating is carried out at a temperature of from 110 to 160° C. and a pressure of from 1 to 15 MPa.
 9. The process of claim 1, wherein the diol is selected from the group consisting of 1,2-ethanediol, 1,3-propanediol, 1,4-butanediol, 2 methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol, diethylene glycol, triethylene glycol, polyethylene glycols, polypropylene glycols such as 1,3-polypropylene glycol, polytetrahydrofuran, 2,5-(dimethanol)-furan and diethanolamine.
 10. The process of claim 1, wherein, in formula (I), Y is F, Cl or Br.
 11. The process of claim 10, wherein Y is Cl.
 12. The process of claim 11, wherein, in formula (I), L³ is CO. 